IN THE PIPELINE: Less Is More In Boston Sci Stent Plans

In a quest for new medicated heart stents, Boston Scientific Corp. (BSX) is aiming for as little medication as possible.

To maintain its heavyweight position in the more than $4 billion market for the tiny heart-artery scaffolds, Boston Scientific must keep pace with a push for stents that still use drugs to keep arteries from reclogging, but don't require long courses of anti-clotting pills.

The Natick, Mass., company recently bought Labcoat Ltd. for this reason. Rather than slathering on polymers and the drugs they attach, the Labcoat system works like an inkjet printer to put tiny amounts where needed.

Medication that stops scar tissue provoked by stent deployment from narrowing arteries is only needed initially. Labcoat devices are designed to shed all their polymer and drug in a matter of months, allowing modest cell coverage to keep stent struts from catching blood cells and creating clots.

"We want to explore the lower limit of drug to get us as close to a bare-metal stent as we can, but maintain the efficacy" of medicated stents, said Keith Dawkins, Boston Scientific's associate chief medical officer.

Doctors see challenges in striking the right balance, and the technology needs validation. But Bernstein Research analysts said they believe Boston Scientific will "become the leading player in the wave of next-generation stents" with polymers that get absorbed by the body.

Labcoat technology can be used on any stent, and Boston Scientific hasn't fully outlined its commercialization goals. Bernstein believes the company - which competes with Abbott Laboratories (ABT), Johnson & Johnson (JNJ) and Medtronic Inc. (MDT) - could reach Europe by late 2009 with Labcoat technology on "Taxus Liberte" stents it already sells, should the company go that route.

Boston Scientific does plan to use Labcoat on a new stent it's developing called Taxus Element, which would come later. It's also studying Labcoat and an internally developed bioabsorbable polymer on stents using the drug "everolimus" and will commercialize one of them.

Early drug-coated stents work well at stopping scar tissue that can lead to repeat procedures, but they put in unnecessary overtime, according to Renu Virmani, a pathologist and well-known critic of coated stents.

Indeed, carpet bombing vessels with drugs while polymers stick around forever may boost the chances for dangerous clots, a realization that badly damaged the stent market in 2006. While the market has regained traction, doctors typically keep patients on the drug Plavix for at least a year to ward off clots.

That is expensive and can create bleeding risks. Boston Scientific wants stents with Labcoat technology that, like bare-metal stents, require anti-clotting drugs for just a month, Dawkins said.

Virmani thought early stage Labcoat study results looked good. But she remains cautious because she believes the drug "paclitaxel" on Boston Scientific's older stents - which it will continue using on new devices - has an unproven track record when used in minute amounts.

Virmani, who is also president and medical director of the CVPath Institute in Maryland, which researches heart disease, has studied how the body responds to stents.

Medicated devices are used today in about three-quarters of U.S. stent procedures, and bare-metal stents are used when patients aren't likely to stick with anti-clotting drugs. It will take clear evidence that new coated stents are safe without those drugs to notably grow usage, said Fred Resnic, who directs the cardiac catheterization laboratory at Brigham and Women's Hospital in Boston.

The industry is chasing this goal.

J&J has a stent in testing that also sheds its polymer and becomes a bare-metal device. Called "Nevo," the J&J device performed well in a study matching it up against a Boston Scientific stent and could hit Europe in 2010.

Abbott is working on devices made entirely of material the body can absorb once scaffolding is no longer needed. Some smaller companies including Biosensors International Group Ltd. (B20.SG), meantime, are already selling metal stents overseas with bioabsorbable polymers.

Regarding the competition, Boston Scientific's Dawkins noted the company sees fully bioabsorbable stents like Abbott's as a likely future technology, but "further down the line." He also noted that the Labcoat technology will use one-tenth the drug and polymer J&J is using on its Nevo stents.

-By Jon Kamp, Dow Jones Newswires; 617-654-6728; [e-mail]